Artificial intraocular lenses, used to replace damaged or diseased natural lenses in the eye, have been widely used in the last several years. Typically, these artificial intraocular lenses comprise some type of optical lens and a support coupled to the lens for positioning the optical lens in the proper location in the eye.
These lenses have typically included hard polymeric or glass optical elements with metallic or polymeric supports. A significant problem with hard lenses is that the incision in the eye through which they are inserted must be at least as large as the diameter of the optical element of the lens. This can be up to six millimeters in length. Thus, the patient must experience a fairly traumatic large incision.
Soft, foldable polymeric lenses have been used but their acceptance has been hampered because it is difficult to support them without sagging and the resulting optical distortion, and it is difficult to insert them into the eye. U.S. Pat. Nos. 4,615,702 and 4,702,865 issued to the applicants herein do indeed disclose soft, foldable artificial polymeric lenses which resist sagging and distortion; however, they still require a relatively large incision, on the order of 4.0 to 4.5 millimeters.
Use of soft hydratable lenses, which are very hard when dry and soft after hydration, would be advantageous; however, it is difficult to support these lenses in the eye without sagging and distortion.
Another problem involving intraocular lenses is that they are typically not easily replaceable. Once installed, the tissue inside the eye tends to grow around the supporting structure and thus it is highly traumatic to remove the lens assembly. This would be exceptionally advantageous in both young and old people whose vision requirements vary as they grow older.
Thus, there is a continuing need for improvement in artificial intraocular lenses.
Examples of prior art intraocular lenses are disclosed in the following U.S. Pat. Nos. 4,073,014 to Poler; 4,159,546 to Shearing; 4,242,760 to Rainin; 4,573,998 to Mazzocco; and 4,615,702 and 4,702,865 to Koziol et al. Examples of prior intraocular lenses are also disclosed in United Kingdom patent application GB No. 2114315 A to Mazzocco, and United Kingdom patent application GB No. 2124500 A to Mazzocco.